Storage racks

ABSTRACT

Pigeonhole-type storage racks, shelves, stands and the like constructed of a plurality of interlocking duplicate members, preferably of precast or extruded concrete.

United States Patent 211/178, 148; 52/79, 236, 610, 604, 605, 608-609, 596, DIG. 2; 46/26, 25, 24, 23; 312/257, 263, 108, 111, 107, 117; 35/72, 69, 34; 108/91 Martin Jan. 18, 1972 [54] STORAGE RACKS 2,699,128 1/1955 Johnson ..46/25 ux 3,107,012 10/1963 Rothenborg.. ..211/11 [72] 3,401,993 9/1968 Fenkel ..312/111 [73] Assignee: McNeil Corporation, Akron, Ohio 3,422,588 1/1969 Stewart ..46/25 X [22] Filed: Sept 12,1969 3,510,997 5/1970 Ratych ..52/79 [21] APPLNQ, 857,439 FOREIGN PATENTS OR APPLICATIONS 1,029,165 3/1953 France ..52/610 52 u.s.c1 ..211/177, 52/79,52/610 1,108,777 9/1955 France 111/148 51 Int. Cl. ..A47rs/00 1,441,807 5/ 1966 France 5s FieldoiSearch ..211/177,1o-11,

Primary E xaminerRamon S. Britts Attorney-n-watts, Hoffman, Fisher & Heinke [57] ABSTRACT [56] Reierences Cned Pigeonhole-type storage racks, shelves, stands and the like UNITED STATES PATENTS constructed of a plurality of interlocking duplicate members,

preferably of precast or extruded concrete. 14,208 2/1856 Terry ..52/604 481,243 8/1892 Orr ..52/610 X 8 Claims, 5 Drawing Figures 2 c 13 D i ,yell

PATENIEBJW 3.635.354

sum 2 or 3 INVENTOR. STUAR 4 MAE'T/A/ ATTOIZNEYE.

PATENTED JANI 819? 3, 635. 354

' sum 3 or 3 INVENTOR. 5711/4/27 A. MART/N BY 9%, Q/ MM ATTORNEYS.

Fig. 5

1 STORAGE RACKS TECHNICAL FIELD This invention relates to pigeonhole-type storage racks, shelves, stands and the like.

SUMMARY OF INVENTION This invention provides a pigeonhole-type storage rack, stand or the like constructed for the most part of a plurality of interlocking duplicate members, preferably precast, extruded or molded and made of concrete, having at least two parts orientated at right angles to each other, assembled together without the use of hand tools, and which racks, etc., may be free standing and can be readily sized or expanded as required.

DESCRIPTION OF DRAWINGS FIG. 1 is a fragmentary perspective view of a storage area having pigeonhole racks embodying the present invention;

FIG. 2 is a fragmentary enlarged view of the near end of the right-hand rack shown in FIG. 1;

FIG. 3 is a view similar to FIG. 2, but showing a different embodiment of the invention;

FIG. 4 is a view similar to FIG. 2, but showing a further embodiment of the invention; and

FIG. 5 is a view similar to FIG. 2, but showing a further embodiment of the invention.

DESCRIPTION OF INVENTION From the foregoing description of the drawings it will be evident that the invention can be embodied in various constructions. The embodiments shown and described in detail herein are merely illustrative of the many possible embodiments and there is no intention to limit the invention to the illustrated embodiments.

The storage area illustrated in FIG. 1 may be a warehouse or merely an area in a factory or the like. The area includingthe storage racks are, in the illustration, serviced by a so-called stacker crane." Alternatively the storage area and/or racks could be serviced manually or by other suitable power-actuated material handling apparatus, for example, so-called fork lift trucks," preferably of the side-loading type.

The racks shown in FIG. 1 are designated R, R, R and R, are of the pigeonhole type, and are arranged facing one another with service aisles between each two adjacent racks. The racks R and R are duplicates of one another, as are the racks R and R. While the racks R and R are shown twice as wide as the other racks it will be apparent that one or more racks of any size may be employed.

The stacker crane shown, designated generally by the reference character C, is of commercial construction, is of the floor supported, self-drive type guided in its travel along the racks and/or through the aisles between the racks by floor rails and overhead rails 11 suspended from the building superstructure B. The crane C is adapted to be moved from the aisle to another or to a loading station by having its upper end moved into an overhead bridgelike crane carrier A, movable along an overhead runway W suspended from the building superstructure B at the near ends of the racks. The overhead carrier A of the crane C includes mechanism for lifting the crane proper free of the floor to permit movement thereof by the carrier along the near ends of the racks.

The crane C includes an L-shaped load carrier l3 vertically movable along the crane mast 14, which load is provided with a transversely movable load support 15 that can be extended into the pigeonholes or compartments of the racks to place loads therein or remove loads therefrom.

Material handling equipment of the type illustrated is commercially available and is shown in more detail in my copending application, Ser. No. 797,57l, filed Feb. 7, 1969, entitled Material Handling Apparatus; now US. Pat. No. 3,583,583.

The rack R comprises a plurality of duplicate L-shaped members E stacked upon a base member F and upon each other to provide a storage rack comprising a plurality of pigeonholes or compartments each adapted to receive a palletized load P. Each of the members.E comprise two main sides or parts 20 and 22 of approximately equal thickness, arranged with respect to one another like the two sides of a right angle. With the members E in the positions illustrated, the vertical parts 20 form the vertical sidewalls of adjoining side by side pigeonholes and the horizontal parts 22 of the tops and bottoms of vertically arranged pigeonholes.

The vertical part 20 of each of the members E is provided with a flange 24 which may be considered as an extension or continuation of the horizontal part 22, and directly opposite the vertical part 20 the top side of the member or the top side of the part 22 is provided with an inverted V-shaped interlock tongue or ridgelike projection 26. The projection 26 preferably extends the length of the member E. The righthand end 28 of the horizontal part 22 is offset vertically in an upwardly direction with respect to the left-hand end thereof a distance equal to the thickness of the part proper, has a thickness greater than that of parts20, 22 of the member E. and has formed therein vertically aligned top and bottom V- shaped interlock apertures or grooves, 30 and 32, respectively. The lower or bottom side of the verticalpart 20 is beveled and terminates in a downwardly projecting V-shaped interlock tongue or ridge 34. The bevel along the-lower edges of the vertical part 20 could be omitted if desired. In this event the lower edge of the part 20 would interlock or interengage with the member therebelow and form the interlocking or interengaging projection of the member.

The construction of the members E is such that when the members are stacked in horizontal rows one upon the other the lower portion of the vertical part'20 of the member being stacked engages in the aperture or groove 30 in the top side of the offset part 28 of the member E in the horizontal row below and in the vertical row immediately to the left of the vertical row in which the member is being placed. The groove 32 in the bottom side of the offset part 28' of the member being stacked engages over the tongue or ridge 26 of the member immediately to the right and in the same horizontal row. The member E being stacked when in position, together with the horizontal part 22 of the member E immediately below and the vertical part 20 of the member E'immediately to the right form a pigeonhole. The portions of the parts '28 at facing or adjoining sides of adjacent vertical parts 20 provides shelves or supports for receiving the load P, shown in phantom lines, placed thereon by the load carrier 15. The top sides of the parts 28 are sufficiently high above the top of the main portion of the part 22 to allow the load carrier to move freely into and out of the pigeonholes underneath a load therein. Similar load supporting ridges 40 are provided in the upper side of the base member F.

The floor or base member F has, in addition to the load-supporting ridge 40, a plurality of horizontally spaced grooves 36 in its upper surface into which the tongues or ridges 34 of the first horizontal row of members E engage. Because there are no members, comparable to the members E, at the left of the left or near terminal vertical row of pigeonholes. small members H, similar in construction to the offset parts 28 of the members E, are provided for interposition between the lower or bottom sides of the vertical parts 20 of the members E which form the left-hand end of the rack, with the exception of the vertical part 20 of the lower member E, the lower end of which merely engages in the left end or near V-shaped groove 36 of the base member F.

Since there are no members to the right of the right terminal vertical row of pigeonholes, members E, which are generally similar to the members E, are used toconstruct the-terminal right-hand vertical row of members. The members E are each generally U-shaped in cross section having vertical parts 42 projecting downwardly from the horizontal part 22 which corresponds to the horizontal part 22 of the member E. The

vertical parts 42 are constructed similarly to and takes the place of the vertical parts 20 of the members E if the rack was to be extended to the right. The parts of the members E, not herein specifically referred to, are identified on the drawings with the same reference characters as those employed for the corresponding parts of the members E, but with a prime mark afiixed thereto.

in forming the rack R, after the base member F has been placed in the desired location, stacking of the members E and E is begun by first positioning the lower right-hand member E on the base member F. The stacking then proceeds in an obvious manner. The members E and E' can be stacked upon the base member and upon one another by use of the stacker crane shown, if desired. As illustrated in FIG. 1, a member E to be positioned in a rack can be placed upon a member 42 on the transversely movable load support of the vertically movable load carriage 13 at a loading station and moved by the crane to its position in the rack. Alternatively, the members E and E can be stacked in any suitable manner, for example, by hand or by use of a fork lift truck of the character previously mentioned.

The rack R is a duplicate of the rack R, previously described, with the exception of the fact that the members thereof which correspond to the members E and E of the rack R are twice as long as the members E and E.

The members E, E', F and H, as shown, are made of precast concrete. However, they may be made of any suitable material other than concrete, for example, fiber glass, plastic, etc., and formed in any desired manner as by casting, extruding, molding, etc. When made of concrete they are preferably reinforced by having steel mesh or rods embedded in the concrete.

The interlocking tongue and grooves, described, lock the members together forming a free standing rack which may be built to any desired height or added to as required. The rack may be readily disassembled and moved to another location, if desired, and when made of precast concrete is fireproof. An integral construction may be produced by using a thin layer of suitable adhesive or cement in the joints during building of the rack.

The rack 2R, shown in FIG. 3, is constructed of members 2E, 2E, 21-! and 2F comparable to the members E, E, and F and H of the rack R, but of different construction. Like the members E of the rack R the members 2E of the rack 2R are precast L-shaped members having two main parts or sides 50, 52 of approximately equal thickness at right angles to one another like the two sides of a right angle. With the members E in the positions illustrated, the vertical parts 50 form the vertical sidewalls of adjoining side-by-side pigeonholes and the horizontal parts 52 the tops and bottoms of vertical arranged pigeonholes. The vertical part of each of the members 2E is provided with a flange 54 similar to the flange 24 of the member E, and directly opposite the vertical part 50 the top side of the member or the top side of the part 52 is provided with an inverted V-shaped interlock groove 56 preferably extending the length of the member 2E. The right-hand end 58 of the horizontal part 52 is offset vertically in an upwardly direction with respect to the left-hand end thereof a distance approximately equal to the thickness of the part proper, has a thickness approximately equal to that of the parts 50, 52 of the member 2E, and has formed therein a vertically aligned top and bottom V-shaped interlock groove and tongue or ridge 60 and 62, respectively. The groove 60 is wider than the thickness of the lower or bottom end of the vertical part 50.

The construction of the members 2E is such that when the members are stacked in horizontal rows one upon the other the lower end of the vertical part 50 of the member being stacked constitutes a projection on the member which engages in the groove or aperture 60 in the top side of the offset part 58 of the member 2E in the horizontal row below and in the vertical row immediately to the left of the vertical row in which the member is being placed. The tongue 62 in the bottom side of the offset part 58 of the member being stacked engages in the groove 56 of the member immediately to the right and in the same horizontal row. The portions of the parts 58 at facing or adjoining sides of adjacent vertical parts 50 are not necessarily high enough to receive a load P on the load carrier 15, and in this instance the top sides of the parts 52 of the members 2E and 2F are provided with horizontal ribs 70, 72 sufficiently high above the top of the main portion of the part 52 to allow the load carrier to move freely into and out of the pigeonholes underneath a load therein.

Because there are no members, comparable to the members 2E, at the left of the near terminal vertical row of pigeonholes, small members 2H, similar in construction to the offset parts 58 of the members 2E, are provided for interposition between the lower or bottom sides of the vertical parts 50 of the members 2E which form the left-hand end of the rack, with the exception of the vertical part 50 of the lower member E, the lower end of which merely engages in the left end or near V- shaped groove 66 of the base member 2F. Obviously, the load support 15 of the crane C must be so constructed as to be projectable into the pigeonholes between the ribs 70 and 72.

Since there are no members to the right of the right terminal vertical row of pigeonholes, members 2E, which are generally similar to the members 2E, are used to construct the terminal right-hand vertical row of members. The members 25' are each generally U-shaped in cross section having vertical parts 74 projecting downwardly from the horizontal part 52' which corresponds to the horizontal part 52 of the member 2E. The vertical parts 74 are constructed similarly to and takes the place of the vertical parts 50 of the members 2E if the rack was to be extended to the right. The parts of the members 2E, not herein specifically referred to, are identified on the drawings with the same reference characters as those employed for the corresponding parts of the members 2E, but with a prime mark affixed thereto. The members which make up the rack 2R are assembled to build the rack in a manner similar to that in which the corresponding members are assembled to build the rack R.

The rack 3R, shown in FIG. 4, is formed of a multiplicity of duplicate members 3E, 3E and 313" of inverted U-shape, somewhat similar to the right-hand terminal members of the previously disclosed racks, stacked up on base members 3F. The lower portions of the vertical parts 80, 82 of the members 3E constitute projections adapted to engage in apertures or channels 92, 90, respectively, formed along the left and righthand edges of the top sides of the horizontal parts 94 of the members in the horizontal row of members therebeneath. As illustrated, the upper portions of the vertical parts 80, 82 of the members 3E are enlarged or flared, as viewed in transverse cross section, so as to better accommodate the apertures or grooves 90, 92, etc., and to provide projections or raised portions 96, 98 for the reception of a load. In this latter respect the raised portions 96, 98 are similar to the raised portions 28 of the members E of the rack illustrated in H6. 2.

The members 3E of the rack 3R, in any horizontal row, are spaced from one another such that the two vertical parts 80, 82 of a member in an upper row rest upon the top adjacent edges of two spaced members in the row below with the result that the horizontal parts 94 of the members in any vertical row are spaced apart a distance equal to twice the height of the members 3E with the parts 94 alternating or offset with respect to one another in adjoining vertical rows. Each pigeonhole, however, is constructed to receive two loads since there are two pairs of spaced load receiving abutments 96, 98 in each pigeonhole.

A rectangularly shaped rack, such as, the rack 3R shown, may be constructed by using in the terminal left and right vertical row members, such as, the members 3E and 3E'. These members are similar to the members 3E except that their left and right-hand vertical sides, and 82, respectively, are twice as high as the sides 80 and 82 of the members 3E and have flared parts intermediate their ends forming abutments 96' and 98' to cooperate with the opposite abutments in the same opening for receiving a load.

The base member 3F is generally .similar to the base member F, shown in FIG. 1, except that the apertures or grooves 100therein, which receive the projecting lower ends of the vertical sides of the members 3E are formed in the top side of raised ribs 102, the upper surfaces of which form loadsupporting abutments for the reception of loads placed adjacent to the base member. The top of the stack can be tied together by a plurality of platelike members it having downwardlyprojecting tongues or ridges 104, 106 along the left and right-hand parts, respectively, of the undersides thereof, as viewed in FIG. 4, which ridges engage in the grooves in the top sides of adjoining members 3E, 3E and 315", as the case may be. The rack SR is formed by first locating the base member on a suitable support and then stacking the members'SE, 3E and 3E" thereon and upon one another in a manner similar to that in which the members forming the previously described embodiments are stacked.

ln the embodiment of the-invention shown in FIG. 5, the rack 4R is formed of a plurality of duplicate members 4E, 4M stacked upon a base member 4F. The members 4B are tubular members generally rectangular in cross section having left and right sides 110, 112 and top and bottom sides 114, 116. The lower left and right corners 120, 122 of the members 413 are relieved, as indicated in the drawings, so that as the members are stacked one upon the other the right and left-hand corners of the members 4E, in the row immediately therebelow, are received in or interengaged in the apertures thus formed. The top side of the part 114 of. each of the members 4E is provided with upstanding projections or ridges 124,126 along their left and right-hand edges but spaced slightly inwardly thereof a distance equal to the thickness of the vertical walls of the members 4E to receive and interengage with the adjacent corners of the member 4E immediately thereabove. In view of the fact that there are no members 4E to form the outside wall of the terminal vertical pigeonholes above the bottom row, these walls are formed in alternate pigeonholes by the members 4M which are platelike in form and have their upper edges received and secured in the lower cutout portions or apertures in the members 4E immediately thereabove and their lower edges received adjacent to and interengag'e with either the projection or ridge 124 or the projection or ridge 126 of the member 4E immediately therebelow depending upon whether the left or the right-hand terminal row of members 4B is referred to. The upper and lower ends of the members 4M can be secured, as by adhesive or cement to the members 4E. The base member 4F has on its top side a plurality of transversely extending projections or ridges 130, 132, 134, 136 for locating and interengaging with the lower row of members 4E thereon and forming abutments for the reception of loads placed in the pigeonholes formed by adjacent members 4E resting upon the base member F.

In forming the rack 4R the base member 4F is located on a suitable support and the other members assembled thereon in a manner which it is believed is obvious from the description of the previous embodiments of the invention shown in FIGS. 1 to 4. The members 413 above can be assembled on the base member 4F to form a rack. It is to be understood that the members forming the racks R3 and R4 can be constructed of any suitable material including-the materials previously men-.

tioned and formed in any suitable manner as by precasting, extruding, etc.

From the foregoing description of the preferred embodiment of the invention shown, it will be apparent that new and improved pigeonhole-type storage racks have been provided which are made up for the most part from a plurality of interlocking and/or engaging duplicate members which can be conveniently constructed at minimum expense and assembled together to form a rack without the use of tools. While a number of preferred embodiments of the invention have been illustrated and described, the invention is not limited to any of the constructions shown and it is the intention to cover all adaptations, modifications and uses of the invention coming within the practice of those skilled in the art to which the invention relates.

lclaim: i

1. A nonmetallic structural unit for assembly with other structural units to form a pigeonhole rack, said structural unit comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part formed integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, a narrow portion of said first part along the other of said edges being offset from the adjacent portion of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part and is spaced therefrom to the side opposite said second part, and said offset portion of said first part having a locking aperture therein spaced from the edge of said offset portion and extending the length thereof on the side opposite the side of said first part from said second part.

' 2. A nonmetallic structural unit for assembly with other structural units to form a pigeonhole rack, said structural unit comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part fonned integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, a narrow portion of said first part along the other of said edges being offset from the adjacent portion 'of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part and is spaced therefrom to the side opposite said second part, and said offset portion of said first part having a locking aperture therein spaced from the edge of said offset portion and extending the length thereof on the side opposite the side of said first part from said second part and a locking means, i.e., aperture or projection, on the opposite side thereof.

3. A nonmetallic structural unit for assembly with other structural units to form a pigeonhole rack, said structural unit comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part formed integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, said first part having a locking means, i.e., aperture or projection, along said one edge but spaced therefrom at the side of said part opposite said second part, a'narrow portion of said first part along the other of said edges being offset from the adjacent portion of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part and is spaced therefrom to the side opposite said second part, and said offset portion of said firstpart having a locking aperture therein spaced from the edge of said offset portion on the side opposite the side of said firstpart from said second part.

4. A nonmetallic structural unit for assembly with other structural units to form a pigeonhole rack, said structural unit comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part formed integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, said first part having a locking means, i.e.,- aperture or projection, along said one edge but spaced therefrom at the side of said part opposite said second part, a narrow portion of said first part along the other of said edges being offset from the adjacent portion of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part and is spaced therefrom to the side opposite said second part, and said offset portion of said first part having a locking aperture therein spaced from the edge of said offset portion on the side opposite the side of said first part from said second part and a locking means, i.e., aperture or projection, on the opposite side thereof.

5. A storage rack comprising nonmetallic structural units assembled vertically and horizontally in side-by-side parallel relation to one another with udjoiningunits in one horizontal row spaced from one another and supporting opposite sides of a unit in the row immediately thereabove, each of a plurality of said units comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part formed integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, a narrow portion of said first part along the other of said edges being offset from the adjacent portion of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part and is spaced therefrom to the side opposite said second part, said offset portion of said first part having a locking aperture therein spaced from the edge of said offset portion and extending the length thereof on the side opposite the side of said first part from said second part receiving a portion of a second unit adjacent thereto.

6. A storage rack comprising nonmetallic structural units assembled vertically and horizontally in side-by-side parallel relation to one another with adjoining units in one horizontal row spaced from one another and supporting opposite sides of a unit in the row immediately thereabove, each of a plurality of said units comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part formed integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, a narrow portion of said first part along the other of said edges being offset from the adjacent portion of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part and is spaced therefrom to the side opposite said second part, and said offset portion of said first parthaving a locking aperture therein spaced from the edge of said offset portion and extending the length thereof on the side opposite the side of said first part from said second part receiving a portion of a second unit adjacent thereto and a locking means, i.e., aperture or projection, on the opposite side thereof engaging a portion of a third unit adjacent thereto.

7. A storage rack comprising nonmetallic structural units assembled vertically and horizontally in side-by-side parallel relation to one another with adjoining units in one horizontal row spaced from one another and supporting opposite sides of a unit in a row immediately thereabove each of a plurality of said units comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part formed integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, said first part having a locking means, i.e., aperture or projection, along said one edge but spaced therefrom at the side of said part opposite said second part, a narrow portion of said first part along the other of said edges being offset from the adjacent portion of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part and is spaced therefrom to the side opposite said second part, and said offset portion of said first part having a locking aperture therein spaced from the edge of said offset portion on the side opposite the side of said first part from said second part receiving a portion of a second unit adjacent thereto and a locking means, i.e., aperture or projection, on the opposite side thereof engaging a portion of a third unit adjacent thereto.

8. A storage rack comprising nonmetallic structural units assembled vertically and horizontally in side-by-side parallel relation to one another with adjoining units in one horizontal row spaced from one another and supporting opposite sides of a unit in the row immediately thereabove, each of a plurality of said units comprising a first rectangular platelike part, second and third rectangular platelike parts at one side of said first part formed integral with said first part adjacent to two parallel longitudinal edges thereof and extending at right angles to said first part, said first part having a narrow rib with a planar ridge along each of said edges and at the side of said first part opposite said second and third parts having an aperture therein spaced from the edges of the ridge extending the length thereof, said apertures receiving portions of second and third units adjacent thereto. 

1. A nonmetallic structural unit for assembly with other structural units to form a pigeonhole rack, said structural unit comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part formed integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, a narrow portion of said first part along the other of said edges being offset from the adjacent portion of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part and is spaced therefrom to the side opposite said second part, and said offset portion of said first part having a locking aperture therein spaced from the edge of said offset portion and extending the length thereof on the side opposite the side of said first part from said second part.
 2. A nonmetallic structural unit for assembly with other structural units to form a pigeonhole rack, said structural unit comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part formed integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, a narrow portion of said first part along the other of said edges being offset from the adjacent portion of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part and is spaced therefrom to the side opposite said second part, and said offset portion of said first part having a locking aperture therein spaced from the edge of said offset portion and extending the length thereof on the side opposite the side of said first part from said second part and a locking means, i.e., aperture or projection, on the opposite side thereof.
 3. A nonmEtallic structural unit for assembly with other structural units to form a pigeonhole rack, said structural unit comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part formed integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, said first part having a locking means, i.e., aperture or projection, along said one edge but spaced therefrom at the side of said part opposite said second part, a narrow portion of said first part along the other of said edges being offset from the adjacent portion of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part and is spaced therefrom to the side opposite said second part, and said offset portion of said first part having a locking aperture therein spaced from the edge of said offset portion on the side opposite the side of said first part from said second part.
 4. A nonmetallic structural unit for assembly with other structural units to form a pigeonhole rack, said structural unit comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part formed integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, said first part having a locking means, i.e., aperture or projection, along said one edge but spaced therefrom at the side of said part opposite said second part, a narrow portion of said first part along the other of said edges being offset from the adjacent portion of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part and is spaced therefrom to the side opposite said second part, and said offset portion of said first part having a locking aperture therein spaced from the edge of said offset portion on the side opposite the side of said first part from said second part and a locking means, i.e., aperture or projection, on the opposite side thereof.
 5. A storage rack comprising nonmetallic structural units assembled vertically and horizontally in side-by-side parallel relation to one another with adjoining units in one horizontal row spaced from one another and supporting opposite sides of a unit in the row immediately thereabove, each of a plurality of said units comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part formed integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, a narrow portion of said first part along the other of said edges being offset from the adjacent portion of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part and is spaced therefrom to the side opposite said second part, said offset portion of said first part having a locking aperture therein spaced from the edge of said offset portion and extending the length thereof on the side opposite the side of said first part from said second part receiving a portion of a second unit adjacent thereto.
 6. A storage rack comprising nonmetallic structural units assembled vertically and horizontally in side-by-side parallel relation to one another with adjoining units in one horizontal row spaced from one another and supporting opposite sides of a unit in the row immediately thereabove, each of a plurality of said units comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part formed integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, a narrow portion of said first part along the other of said edges being offset from the adjacent portion of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part aNd is spaced therefrom to the side opposite said second part, and said offset portion of said first part having a locking aperture therein spaced from the edge of said offset portion and extending the length thereof on the side opposite the side of said first part from said second part receiving a portion of a second unit adjacent thereto and a locking means, i.e., aperture or projection, on the opposite side thereof engaging a portion of a third unit adjacent thereto.
 7. A storage rack comprising nonmetallic structural units assembled vertically and horizontally in side-by-side parallel relation to one another with adjoining units in one horizontal row spaced from one another and supporting opposite sides of a unit in a row immediately thereabove, each of a plurality of said units comprising a first rectangular platelike part, a second rectangular platelike part at one side of said first part formed integral with said first part adjacent to one of two parallel longitudinal edges thereof and extending at right angles to said first part, said first part having a locking means, i.e., aperture or projection, along said one edge but spaced therefrom at the side of said part opposite said second part, a narrow portion of said first part along the other of said edges being offset from the adjacent portion of said first part such that the midplane thereof is parallel with the plane of the remainder of said first part and is spaced therefrom to the side opposite said second part, and said offset portion of said first part having a locking aperture therein spaced from the edge of said offset portion on the side opposite the side of said first part from said second part receiving a portion of a second unit adjacent thereto and a locking means, i.e., aperture or projection, on the opposite side thereof engaging a portion of a third unit adjacent thereto.
 8. A storage rack comprising nonmetallic structural units assembled vertically and horizontally in side-by-side parallel relation to one another with adjoining units in one horizontal row spaced from one another and supporting opposite sides of a unit in the row immediately thereabove, each of a plurality of said units comprising a first rectangular platelike part, second and third rectangular platelike parts at one side of said first part formed integral with said first part adjacent to two parallel longitudinal edges thereof and extending at right angles to said first part, said first part having a narrow rib with a planar ridge along each of said edges and at the side of said first part opposite said second and third parts having an aperture therein spaced from the edges of the ridge extending the length thereof, said apertures receiving portions of second and third units adjacent thereto. 